John Calvert, who became the master of the Worshipful Company of Turners in 1819, was one of the top chess set makers in England. He worked from 1791 until his death in c.1825, with his widow Dorothy running the business until 1840.
This particular pattern, sometimes dubbed the John Calvert Tournament style, was also made by Thomas and William Lund as well as George Merrifield and John Jaques. It was one of the many English sets that were ultimately supplanted by the Staunton pattern introduced in 1849.
This set in boxwood and ebony with 4in (10cm) kings probably dated from c.1820 and was offered with a board of a similar date. Despite a couple of repairs to two pawns, it checked out for £2500.